Electropneumatic throttle control



Aug. 9, 1932. R, M. DlLwoRTH ELECTROPNEUMATIC THROTTLE CONTROL Filed Jan. 19, 1931 ATTR EY5 Patented Aug. 9, 1932 uNrrs` srrss PATENT oFFlcE n RICHARD M. DILWORTH, OF LAKEWOOD, OHIO, ASSIG-NOR, TO THE ELECTRO-MOTIVE COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO ELECTROPNEUMATIC TI-IRDTTLE CONTROL Application ledpJanu'ary 19, 193-1. .Serial No. 509,613. Y

This invent-ion relates to control means for the throttle of an internal combustion engine, the means being of the so-called electro-pneumatic type whereby remote control of the throttle may be had as is desirable in certain internal combustion installations such as in locomotive or marine practice.

The electro-pneumatic throttle control is not new per se, and as will be appreciated by one familiar with the art comprises a number of pistons usually single-acting and springbalanced to rest position and movable from the latter under air pressure, these pistons being associated with the throttle of the engine to be controlled by a differential-arrangement whereby the throttle may be opened step by step, by admission of air to the pistons in succession. Such admission is Acontrolled by a number of valves one for each piston, and for remote control the valves are in turn controlled each by electric means. Usually a controller is provided for the purpose whereby the valves are related for opening in a predetermined sequence to progressively open the throttle by movement of the controller in one direction.V

Thus the entire control respectively includes three systems arranged: the iirst, a

. mechanical one including the differential inthrottle; and if the compressor at idling7 speed has not suicient delivery overy leakage in the system it will be apparent that, as after a long period of idling, the pneumatic control mustV bedisconnected and the throttle opened by hand, before the compressor can supply enough air for normalv pneumatic control. Such has heretofore been the practice in the art and the elimination of the necessity for such practice is the principal object of this invention.

Briefly, I accomplish this by so vassociating the pistons with the throttle that the throttle is partially open when the pistons are in rest position, one of the pistons beingidling arranged to close the throttle to position only under pressure from the pneumatic system. By this arrangement Whenthe operator sets his controller or other operator-operated means to idle position the engine throttle will be moved correspondingly Vand will so remain while there is a normal or predetermined pressure maintained in the pneumatic system. But should this pressure at any time and for any reason become insuiiicient, the throttle will be automatically opened to increase the output of the compressor; and when the desired pressure has been rebuilt, vthe throttle will automatically reclose to idling position. Thus, at all times the pneumatic. control is maintained operative subject to the will of the operator. a

The exact nature of this invention together with further objectsjand advantages thereof will be apparent from the following description taken in connection with the accompanying drawing, in which Figs. l and 2 are diagrammatic and conventionalized showings of the electric and pneumatic systems respectively; Fig. 3 is a detail showing the lassociation of the pneumatic system with the throttle of the engine to be controlled, by the mechanical or differential arrangement interposed therebetween Fig. 4 is a detail showing the inter-association of the electricv and pneumatic systems; and Fig. 5 is a detail of the electrically controlled valve means employed. In Figs. 2-4 inclusive parts appear in section to show details of construction.

l/Vith reference now to the drawing, 1 rep` l resentsthe throttle valve of theengine to be controlled. The valve is of butterfly type as indicated, mounted for pivotal movement in the inlet pipe 2 of the engine. Slis a lever outside vthe pipe rigidly associated with the valve and 4 is a link pivoted with the lever 3 for operating the latter and thus the valvel.

For operatingthe valve 1A by pneumatic power a. number of pistons are provided. Thus in Fig. 3, four pistons 5, 5a, 5b, 5c, are provided each movable in its cylinder bore piston 5 has connection with one end of the lever 10. The opposite end of Jcihis lever has connection with a link 11 which inrturn has at its opposite end connection with an end of the lever 12, The piston V5?) has connection with the lever l intermediate the ends of the latter by a link 13. The piston 50l hasconnectio'n with one end of `a lever 14 the opposite end of which has Vconnection vwith the piston vc through a link 15.. The lever 14 aov has'connection with the lever 12 intermediate theends of the latter by means of a link 16.

The lever 12 has connection with the link 4 at its end as indicated, so'that the thrott'le 1 may `'be controlled by movement of the lever 12.

The linkage described will be recognized as providing a-diferential relation between the .four pistons and the throttle valve 1 whereby the position of the throttle is a function of `the positions of the several pistons. The lever 1Q is -a floating lever controlled by the pistons .5 and 5b; the lever 14 is .a floating levercontrolled the pistons 5a land 5c; and the lever 12 is a secondary lioating lever controlled by the positions of the levers 10 a-ndf1'4. i

It 'will 'be observed that by this linkage pneumatic operations of all of the pistons does not produce the same eect upon the throttle valve. Movement .of any of the three pistons 5a, 15b or '5c' Yfrom restY position ywill effect opening of .the throttle valve; and coincidentV movement of more than one of these three pistonswill more widely open the throttle valve. But movement of the fourth piston .5 will close the vthrottle valve.

The proportion 'and arrangement of the pains is lsuch that when the pist-onsare all at rest as 'shown 'in Fig. 3 the throttle valve will be Open slightly wider than tor""idl'ing'" of the engine, and such that only when the piston 5 is moved from closed position, can the throttle valve move to idling position.

KTWith reference 'now to 2, 17 represents the engine yto, `-be controlled f; '18, a compressor driven by the engine; 19, a receiver into which the compressor delivers; and 20, the four cylinders inthe Y'block 6 for the pistons 5 shown in Fig. 3. Each cylinderV 20 has communication with the receiver 19 through a manifold passage 21l and its inlet passage 8 subject to :a valve 22. y

l.llVith 'reference now to and 5, each valve is yieldably maintained seated as by a spring 23 to close admission of air from the passage 21 into the passage 8 of its cylinder 20. Each valve has an operating stem 24 with an annular opening 25 thereabout whereby passageway is had tothe Cylinder when the valve is open. On the opposite end of its stem 24 each valve 22 has a second valve 26 movable upwardly to close the lower month, Fig. 15, yof' the passage 25 when the valve 22 is unseated, and to unseat as indicated in Fig. 5 when the valve 22 is seated. The valve 27 is provided with a passage 28 one for each cylinder, whereby relief to atmosphere is had for that cylinder when the valve 22 is seated. In lother words,each valve'stem 24 has two positions, one in which its pistonis subject to pressure from the compressor 18; and in the other of which, its rest positi.on,jits cylinder is relieved to the atmosphere so that its piston is subject .only to itszspring Each valve is controlled by electrical means such as a solenoid 29 having a .coil

30 and an armature controlled by the Acoil and rigidly associated, as integral, with the valve 26. Thus there vare four solenoids., one

for controlling each. piston 5..V As shown in Fig. 1, these four solenoids are arranged in a controller circuit so that theirV coils 30 ,are energized dependent upon the position of .a drum 31. The controller 31 has the usual contactors 32 engageable with lingers 33depcndent upon .the position .of the drinn. The

arrangement of thecontactors 32 upon thev controller 31 is such vthat controller movement will .energize the solenoids 29 ina predetermined sequence .asthe drum is moved in one direction; and thi s sequence is such thatV the floating lever 12 will moveto open orV close the throttle step by step dependent upon the direction of drum movement.

AThe drum is loperator-operated ,and may, of course., be located at a remote position` from the solenoids 29. y l

` Operation will 'be apparent. Vhen the drum is in idling position the valve22 of. the piston Vwill be open but .the valves 22 ofthe other `three pistons 5a, '5t .and .150 will all be closed. The throttle 1, therefore, will be moved to idling position. As the `operator moves the druin 31 from idling position, first the valve 22 .of the piston 5 will be moved to release the piston 5 to the action of its spring 7 and thethrottle '1 willmove toward open position. Further .drum movement will `effect opemnff andclosmg of val-ves 22 in predetermined order to correvzspondingly move the pist-ons l 501, 5b and 5c..

rThe differential linkage may preferably be of such order'that Vby various combinations of opening of the valves ofthe pistons 5a, .5b and 5c., more steps of throttle opening maybe had than there are pistons; but such arrangement is well knowniand indeed im.

material here.

When the drum is set to idling position and the valve 22 of the piston 5 consequently open, the throttle 1 will remain in idling position only so long as there is sufficient pressure in the manifold 21 to maintain the piston 5 against its spring 7. Should the air pressure fall below such amount as by leakage anywhere in the system or by eX- hausting the capacity of the receiver 19, the piston 5 will move to rest position automatically under the action of its spring 7, and the valve 1 will consequently be moved to speed up the engine. The valve 22 of the piston 5 will, however, remain open so that when the compressor 18 has built up the required pressure in the system the piston 5 will be returned by this pressure against its spring 7 reclose thethrottle to idling position and the engine will again be running at the idling speed indicated by the drum position.

What I claim is:

1. In an electro-pneumatic throttle control of the class described, wherein an engine throttle is to be controlled by a plurality of pistons arranged to be separately movable in a Xed sequence from rest position by air from a compressor driven by the engine, differential means associating said pistons with said throttle and providing for partial opening of said throttle when all of said pistons are in rest position, and providing for movement of said throttle to idle position by movement of one of said pistons under air pressure.

2. In combination with an engine having a. throttle and a compressor driven by said engine, control means for said throttle and comprising a plurality of pistons, differential mechanism associating said pistons with said throttle whereby the position of the throttle is a function of the positions of said pistons, operator-controlled means for controlling admission of air from said com.- pressor selectively to said pistons, one of said pistons being arranged for throttleclosing movement under the pressure of said air admitted thereto, and another of said pistons being arranged for throttle-opening movement under the pressure of air admitted thereto.

3. In combination with an engine having a throttle and a compressor driven by said engine, control means for said throttle and comprising a plurality of pistons, differential mechanism associating said pistons with said throttle whereby the position of the throttle is a function of the positions of all of said pistons, operator-controlled means for controlling admission of air from said compressor selectively to said pistons, one of said pistons being arranged for throttleclosing movement under the pressure of said air admitted thereto and having associated means providing for throttle-opening movement in the absence of said pressure, and the other pistons being arranged for throttleopening movement under the pressure of said air admitted thereto.

ll. In combination with an engine having a throttle and a compressor driven by said engine, control means for said throttle comprisinga plurality of single-acting pistons, differential mechanism associating said pistons with said throttle whereby the position of the throttle is a function of the positions of all said pistons, operator-controlled valve means for controlling admission of air from said compressor selectively to said pistons, one of said pistons being arranged' for throttle-closing movement under the pressure of said air admitted thereto, and the other pistons being arranged for throttle-opening movement under the pressure of said air admitted thereto, each of said pistons having associated means providing for, its movement in the opposite Y direction from that effected by air pressure.

5. In combination with an engine having a throttle and a compressor driven by said engine, control means for said' throttle and comprising a plurality of pistons, differential mechanism associating said pistons with said throttle whereby the position of the throttle is a function of the positions of all of said pistons, operator-controlled means for controlling admission of air from said compressor selectively to said pistons, one of said pistons being arranged for throttle-closing movement under the pressure of said air admitted thereto and having associated means providing for throttle-opening movement in the absence Vof said pressure, and the other pistons being arranged for throttleopening movement under the pressure of said.

air admitted thereto, and operator-operated y means associated with said voperator-controlled means for providing for a predetermined sequence of admission to said pistons whereby the progression of admission willv be to effect opening the throttle as the operator-controlled means is moved in o-ne direction, and vice versa.

In testimony whereof I hereby aliix my signature.

l RICHARD M. DILWORTH. 

